148 GEOLOGICAL HISTORY OF THE YELLOWSTONE PARK. 



Silica 0-4685 



Sulph. acid 0923 



Carbonic acid (I vnfiS 



Boracic acid -OSIT 



Arsenious acid -0018 



Chlorine, -5740 



BromiDe Trace 



Hydr. sulpli None 



Oxygen (basic) ' -0048 



Iron I Trace 



Manganese ' None 



Aluminium '0185 



Calcium I 0-0146 



Constant Geyser. 



Grams 

 per kilo 

 of water. 



Magnesium. 

 Potassium . . 



Sodium 



Lithium 



Ammonium . 

 Hydr. (HCl) 



Caesium 



Rubidium . . 



Total . 



-0018 

 -0745 

 -3190 

 -0030 

 -00127 

 -0008 



Per cent 

 of total 

 matter in 

 solution. 



Hygeia Spring 



Grams 

 pel kilo 

 of water. 



28-88 

 5-69 

 -95 

 1-95 

 0-11 



35 -39 



0-29 

 -90 

 O-U 

 4-60 

 19-67 

 0-19 

 0-08 

 0-05 



100 -00 



-2477 

 0-01!)0 

 -2907 

 -0239 

 -0034 

 -2457 

 Trace 

 None 

 -0504 

 None 

 None 

 -0036 

 -0064 

 -0022 

 -0154 

 -2654 

 -0032 

 -00021 



Per cent 

 of total 

 matter in 

 solution. 



20 -98 

 1-65 



•24 -62 

 2-02 

 0-29 



21 -00 



Old Faithful. 



Grains 

 per kilo 

 of water. 



0-31 

 0-54 

 0-19 

 1-30 



22-48 

 0-27 



-3828 

 -0152 

 -0894 

 -0148 

 -0021 

 -4391 

 -0034 

 -0002 

 -0419 

 Trace 

 Trace 

 -0009 

 -0015 

 -0006 

 -0267 

 -3660 

 -0056 

 -00001 



Per cent 

 of totiil 

 matter in 

 solution 



27 -52 

 1 -09 

 6-43 

 1-07 

 0-15 



31-57 

 0-25 

 0-01 

 3-02 



Trace 

 Trace 



0-06 

 0-11 

 0-04 

 1-92 

 26-36 

 0-40 



100 -00 



Constant Geyser, Norris Geyser Basin. Date of collection, September 13, 1885; temperature, 198° 

 F. ; reaction, slightly acid; specific gravity, 1-0011. 



Hygeia Spring, Lower Geyser Basin. Date of collection, September 11. 1885; tcmiioratiire, 109^ F. ; 

 reaction, alkaline; specific gravity, 1-0010. 



Old Faithful Geyser, Uiiper Gey.ser Basin. Date of collection, September 1, 1884; temperature, 100^ 

 F. ; reaction, alkaline; sjiecific gravity, 1-00096. 



They are all siliceous alkaline waters lioldiiig' the same mineral con 

 stituents, but in varying qnautities. SiHca forms the principal deposit 

 not only immediately around the springs, but over the entire floor of 

 the basins. The carbonates, sulphates, chlorides, and traces of other 

 easily soluble salts are carried off in the waters. Oxides of iron and 

 manganese and occasionally some calcite occur under certain condi- 

 tions in the cauldrons of the hot springs or immediately around their 

 vents. Concentrations from large quantities of these waters tail to 

 show the presence of even a trace of copper, silver, tin or other metal. 

 Nearly all the waters carry arsenic, the amount present, according to 

 Messrs. Gooch and Whitfield, varying from .02 to .25 per cent of tbe 

 mineral matter in solution. 



Among the incrustations found at several of the hot springs and 

 geysers is a leek-green amorphous mineral, which proves on investiga- 

 tion to bescorodite, a hydrous arseniate of iron. The best occurrence 

 observed is at Joseph's Coat Springs, on the east side of the Grand 

 Canon of the Yellowstone, where it occurs as a coating upon tlie sili- 

 ceous sinter lining the cauldron of a boiling spring. Analysis shows 



